The World Names Profiler is a database that uses publicly available telephone directory and electoral register data from 2000-2005 to estimate the frequency of surnames in 26 countries. The database includes all countries which we know to have a significant population of people bearing an Eastlake or variant surname except South Africa. Including a small adjustment for our South African branch, the following estimates are available with frequency given as surname occurrences per million of total population. From these frequencies, a rough estimate can be made of about 5500 people living worldwide in the year 2000 with the Eastlake surname or variant.
Australia has the highest frequency of our surnames, essentially all holding the Eastlake or Es(t)lick surnames. The reason for such a high rate of occurrence relative to the general Australian population is examined in the Distribution section. As highlighted in the Surname Map shown in the Variants section, the USA has the most surname variety, not surprising given that it accounts for perhaps 70% of the holders of our surnames. The Eastlack/Estlack variants only survive in the USA, which is also the only place with a sizeable proportion of the Easlick/Eastlick variants. Spain is a newcomer not yet detected in our reconstruction work, perhaps some recent migrations to the Mediterranean sun.
Further detail is available on Great Britain using the GBNames Profiler. Although only the Eastlake and Eslick forms of our name are sufficiently frequent for this type of analysis, the Profiler identifies the following interesting changes from 1881 to 1981:
Our analysis indicates that approximately a third of the increase in the Eastlake frequency and similar decrease in the Eslick frequency may be due to Eslick families changing their name to Eastlake or Estlick. These name changes occurred almost entirely in Great Britain and mostly between 1880 and 1910. Over fifty people were born in this timeframe with such name changes relative to their fathers.
The remainder of the decrease in Eslick frequency is most likely due to emigration, the Eslick surname being prevalent amongst the Cornish miners who joined the diaspora in the latter 1800s upon the collapse of the copper mining industry in England.
In order to determine the progress of the one-name research, it would also be helpful to have an estimate of the number of people born worldwide with the Eastlake or variant surname. Using the estimate above of those living in the year 2000, mortality data, vital records (birth, marriage, death) from Great Britain, census records from North America and Great Britain along with other data from our reconstruction to date, some crude figures are offered based on our current understanding:
Given that the our reconstruction currently consists of approximately 4000 holders of the surnames before 1915 and 1500 after 1915, we estimate that the reconstruction includes about 80% of those born before 1915 but less than 15% of those born since 1915. Over time, it may be possible to cover up to 90% of pre-1915 individuals but privacy constraints for people born since that time make it unlikely that more than about 40% of the most recent surname holders will be identified, primarily those born before 1950.